(57) Biological material such as proteins and microbes is encapsulated by a method which comprises

a) admixing the biological material with an aqueous non-ionic polymer solution in which the polymer is present at a concentration of at least 3% w/v;

b) forming polymeric beads by adding the mixture of part (a) dropwise into a water-immiscible non-solvent for said polymer, said non-solvent being maintained at a temperature sufficient to freeze the bead but not so low to cause freeze fracture; and

c) drying the beads of step (b) to remove substantially all unbound water in said beads.

Freeze-drying produces a stable encapsulated product which in the case of microbes retains a high level of viability. The method provides a means of using microbes as agricultural agents since the encapsulated product is acceptable and useful to the farmer.